Solution pump with supercharged suction for absorption air conditioner

ABSTRACT

A pump for a liquid including a volatile material and particularly adaptable for an absorption refrigeration system with the pump having means for subjecting the liquid at the inlet side of the pump to a supercharged pressure tending to prevent vaporization of the volatile material of the liquid at the intake of the pump.

Unite States Patent 1 51 3,639,087

Frohbieter 1 1 Feb. 1, 1972 [54] SOLUTION PUMP WITH 3,145,914 8/1964 Nicholas ..4l7/203 SUPERCHARGED SUCTION FOR 3,169,696 2/1965 Warner ..4l2/372 ABSORPTION AIR CONDITIONER [72] Inventor: Edwin H. Frohbieter, Stevensville, Mich.

[73] Assignee: Whirlpool Corporation [22] Filed: Oct. 29, 1969 [21] Appl. No.1 872,129

[52] US. Cl ..4l7/572, 417/203 [51] Int. Cl ..F04b 23/14 [58] Field of Search ..4l7/203, 372, 901,200,572

[56] References Cited UNITED STATES PATENTS 2,688,925 9/1954 Thoren et al. ..417/203 3,316,849 5/1967 Cooper et al. ...4l7/90l X 2,780,170 2/1957 Stoyke et al. .412/203 1,797,803 3/1931 Spreen ...417/203 2,509,377 5/1950 Trask ..417/203 FOREIGN PATENTS OR APPLICATIONS 217,044 6/1956 Australia ..4 1 2/203 Primary Examiner-Carlton R. Croyle Assistant Examiner-Richard E. Gluck Attorney-James S. Nettleton, Thomas E. Turcotte, Burton H. Baker, Gene A. Heth, Franklin C. Harter, Anthony Niewyk, Robert L. Judd and Hofgren, Wegner, Allen, Stellman and McCord [57] ABSTRACT A pump for a liquid including a volatile material and particularly adaptable for an absorption refrigeration system with the pump having means for subjecting the liquid at the inlet side of the pump to a supercharged pressure tending to prevent vaporization of the volatile material of the liquid at the intake of the pump.

1 Claims, 2 Drawing Figures SOLUTION lPUMlP WITH SUPERCHARGED SUCTION FOR ABSORPTION AIR CONDITIONER The magnetic coupling drive illustrated herein is disclosed and claimed in my copending application Ser. No. 872,128 filed Oct. 29, 1969, assigned to the same assignee as the present application.

One of the features of this invention is to provide a pump for a liquid including a volatile material with the pump having an intake and means for maintaining the iiquid under a minimum preselected pressure at the intake tending to prevent volatilization or flashing of the volatile material at this intake.

Other features and advantages of the invention will be apparent from the one embodiment shown in the accompanying drawings, of which:

FIG. I is a vertical sectional view through a bottom portion of a pump for an absorption refrigeration liquid.

FIG. 2 is a horizontal sectional view taken substantially along line 22 of FIG. 1.

In the illustrated embodiment the liquid containing pump comprises a casing 11 having a bottom 12 beneath which is positioned a hysteresis member which comprises an annular block 13 of magietically hard material such as ALNICO. This ring-shaped block 13 is positioned closely adjacent the bottom 12 of the casing and is held in an annular holder of nonmagnetic material such as brass, stainless steel or the like.

Located closely adjacent the bottom surface of the annular block 13 is an annular first permanent magnet 15 that is mounted on and movable with a ring-shaped platform 16 that is also nonmagnetic.

The holder 14 for the hysteresis member 13 is attached to a rotatable shaft 17 by a setscrew 18. The shaft 17 may be driven by an electric motor (not shown). Located within the bottom 12 of the casing, which is constructed of a nonmagnetic material such as stainless steel, is a permanent second magnet 119 of circular configuration with the member 13, holder 14, first magnet 15, platform 16, shaft 17 and second magnet 19 all being coaxial.

The first magnet 15 and its supporting platform 16 are rotatable together on a bearing structure 20 that surrounds an axial extension 21 of the drive shaft 17.

The permanent second magnet 19 within the casing 11 is mounted on a top plate 22 which carries a plurality of spaced curved vanes 23 to provide a centrifugal pump.

Extending upwardly from the plate 22 is a pump shaft 24 that is provided with an eccentric slider block 25. Upon rotation of the shaft 24 the block 25 reciprocates in its pump cavity 26 and in so doing reciprocates a piston 27 that is mounted in a piston cylinder 28 formed in a lateral extension 29 to the pump body 30.

The piston 27 which is arranged generally horizontally has a smaller outward extension 31 thereon which extends into a cylindrical cavity 32 in a screwplug 33. This cavity 32 carries a helical compression spring 34 one end of which bears against the outer end of the piston 27. During movement of the slider block 25 the piston 27 reciprocates in its horizontal path. On the inward movement of the piston, or to the left as shown in FIG. I, the pump applies suction by way of passage 35 to refrigerant liquid such as ammonia dissolved in water that is held in the bottom of the casing 11 and which fills the vertical passage 35 as well as the bottom reservoir 36. This reservoir 36 of course has the centrifugal pump formed on plate 22 by vanes 23 immersed therein and liquid is supplied to the pump by way of an annular passage 37 just above the inner ends of the pump vanes 23. This passage 37 leads from an annular chamber 38 that is formed around the lower end of the vertical pump shaft 24 and that is supplied with liquid from the interior of the casing 11. by way of a standpipe 39.

On the suction stroke of the piston 27, or movement to the left, the resulting suction draws liquid upwardly in the passage 35 past the flexible one-way valve 40 which permits flow only in the upward direction. Then, on the reverse movement of the piston 27, the pressure above the valve 40 forces it closed and forces liquid under pressure from the pump into the highpressure portion of the refrigeration system (not shown) as indicated by the discharge liquid flow line 4ll.

On the suction stroke of the piston 27 liquid is drawn through passage 35 and valve 40, reducing the pressure on refrigerant solution within reservoir 36. The refrigerant solution may be at or near its boiling point and thus when the pressure is reduced as a result of the suction stroke of piston 27 the liquid may vaporize within passage 35 or cylinder 28 thus interfering with the pumping action of the pump.

In order to alleviate the vaporization problem within passage 35 and cylinder 28 the centrifugal pump formed by vanes 23 is provided to pressurize the liquid within reservoir 36 thus raising the boiling temperature of that liquid and precluding flash vaporization.

The centrifugal pump requires a minimum operating head in order to pump sufficient liquid to maintain the desired pres sure head on the liquid within reservoir 36. This minimum head is provided by a standpipe 39 which is normally immersed in liquid dumped into casing 11 of the pump from a source such as an absorber of an absorption refrigeration apparatus (not shown).

Because of the height of the standpipe 39 a quantity of liquid is always stored within the casing 11 of the pump 10 with the liquid level never falling substantially below the upper or inlet end of the standpipe 39. When the liquid level rises above this upper end of the standpipe it is of course immediately supplied to the centrifugal pump by way of the standpipe 39. The additional liquid necessary to raise the level in casing 11 to above the inlet of standpipe 39 therefore can be a very small quantity to provide a large liquid pressure head for the centrifugal pump.

This immediate supplying of additional liquid to the centrifugal pump by way of the standpipe 39 with only a relatively small amount of added liquid to the interior of the pump casing 11 permits the piston pump to recover a high discharge head even when it has drawn all of the liquid from within the reservoir 36. This is a very important advantage to the pump of this invention because it will not operate properly when vapor is present at the suction inlet passage 35. With this invention the proper operation of the refrigeration system is maintained at all times because of the ability of the pump to provide a high-pressure head almost instantaneously after liquid is again available to the pump.

Having described my invention as related to the embodiment shown in the accompanying drawings, it is my intention that the invention be not limited by any of the details of description, unless otherwise specified.

I claim:

1. Structure for pumping a liquid having a volatile component, comprising: pump means having an inlet; a reservoir subjacent said inlet; passage means providing communication between said reservoir and said pump inlet; and means including a standpipe extending upwardly from said reservoir to above the level of said inlet for maintaining at least a preselected minimum head pressure on said liquid at said inlet during pumping operation of said pumping structure, said pump means being disposed within a casing defining a chamber for holding said liquid, said standpipe extending upwardly from the bottom of said chamber whereby a quantity of said liquid is maintained in said chamber up to the level of the top of said standpipe.

ins-ma 

1. Structure for pumping a liquid having a volatile component, comprIsing: pump means having an inlet; a reservoir subjacent said inlet; passage means providing communication between said reservoir and said pump inlet; and means including a standpipe extending upwardly from said reservoir to above the level of said inlet for maintaining at least a preselected minimum head pressure on said liquid at said inlet during pumping operation of said pumping structure, said pump means being disposed within a casing defining a chamber for holding said liquid, said standpipe extending upwardly from the bottom of said chamber whereby a quantity of said liquid is maintained in said chamber up to the level of the top of said standpipe. 